Because of being lightweight and having excellent shaping properties, various resins have been used as raw materials for automobile interior and exterior parts such as pillars, door trims and door panels. For example, automobile interior parts such as instrument panels, door trims and door panels have been produced using leather-like finished materials such as acrylonitrile-styrene resins (AS resins) and polypropylene resins (PP resins) coated with soft resin skins such as vinyl chloride, or AS resins and PP resins grained and painted to attain a leather-like texture.
With a recent increase in the demands for the simplification of production steps and the recycling of surplus materials, there is an increasing demand that shaped resin articles which have undergone surface processing such as graining be used as automobile interior and exterior parts without being finished by painting, the application of films or the like. However, uncoated resin articles such as polypropylene resin shaped articles have a problem in that they are prone to be scratched during assembling or use.
Thus, various studies have been made on resin compositions which can give shaped articles having excellent properties required for automobile interior and exterior parts such as shaping properties, rigidity and heat resistance and also exhibiting excellent scratch resistance. For example, fillers are added to increase strength (see Patent Literature 1), resin components with excellent crystallinity are used to enhance hardness (see Patent Literature 2), and talc and scratch improvers are added to polypropylene compositions to obtain high Izod impact strength and high scratch whitening load (see Patent Literature 3). According to these techniques, the resistance to scratching may be enhanced to a certain degree.
However, the problem of the deterioration in surface conditions that is encountered during the actual use of shaped articles as automobile interior and exterior materials is not limited to flaws such as scratches but is also caused when the articles are rubbed with soft substances such as rubbers, for example, when the articles are kicked with shoe soles.